Taha's comment on Tuesday conflicts with the agreement announced in Addis Ababa on Friday, when Sudan and the African Union agreed to extend the mandate of the AU peacekeepers in Darfur to September, and then allow them to be merged into a larger United Nations force.
Referring to the UN force, Taha said "Sudan's stand is to reject those forces even when the period of six months has elapsed".
He did not explain how the government reconciled that position with its acceptance of the Addis Ababa accord.
Separately, Omar al-Bashir, the Sudanese president, criticised the African Union decision to extend its peacekeeping mission in Darfur up to next September.
"Invisible hands" have added items to the AU decision that were not part of the original agenda for discussion, he said.
The Khartoum government has long opposed a UN force replacing the AU mission in Darfur, western Sudan, where a three-year conflict has led to the deaths of at least 180,000 people and the displacement of another two million in what the US calls "genocide."
The US and the European Union have been pushing for a big UN mission in Darfur, believing that the 7000 personnel of the AU force were too thin on the ground to bring a halt to the violence and protect the humanitarian agencies distributing relief.
Under Friday's deal, the AU mission, which is due to expire this month, was extended through 30 September, when it would be succeeded by a UN force.
The agreement gives more time both for the government and Darfur rebels to negotiate peace, and for the UN to prepare a large peacekeeping force.